Conversion of dietary choline to trimethylamine and dimethylamine in rats: dose-response relationship.

摘要: Trimethylamine (TMA) and dimethylamine (DMA) are normal components of human urine precursors dimethylnitrosamine, a potent carcinogen. In part, DMA TMA products the metabolism dietary choline by intestinal bacteria. Most formed in tract is later oxidized excreted as trimethylamine oxide (TMAO). Humans treated with large doses smell "fishy" (the odor TMA). ingest part foods, yet rarely fishy, suggesting that formation must depend upon dose ingested. We found that, adult rats, at low (1.5 mmol/kg body wt) only 9 mumol (6% dose) reached intestine which colonized bacteria cecum colon). After administration 15 mmol choline/kg wt, 237 (16% colon. At both doses, 64-65% administered was absorbed from 3 h after dose. orally slightly increased TMAO excretion smaller than 7 but there disproportionately increase per 24 when larger were (from 11 100 kg wt controls to 226 3617 rats wt).(ABSTRACT TRUNCATED AT 250 WORDS)